Accumulator n. : One who, or that which, accumulates, collects, or amasses.

Accumulator n. : An apparatus by means of which energy or power can be stored, such as the cylinder or tank for storing water for hydraulic elevators, the secondary or storage battery used for accumulating the energy of electrical charges, etc.

Accumulator n. : A system of elastic springs for relieving the strain upon a rope, as in deep-sea dredging.

Example:
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Taxonomy
Accumulator, free encyclopedia, storing energy, electrical energy, energy storage device, search, free dictionary, processor register, intermediate results, apparatus, power, electrical engineering, obsolete term, stores, rechargeable batteries, hydraulic fluid, pressure, parlay bet.

Defination from the web:
accumulator ... Dynamic accumulator, a plant that mines nutrients from the soil through its roots. This disambiguation page lists articles associated with the same title. ...